[Objective] To compare the clinical outcomes of percutaneous transforaminal endoscopy (PTE) versus unilateral biportal en-doscopy (UBE) for degenerative lumbar spinal stenosis (DLSS) in the elderly. [Methods] A retrospective research was done on 72 patientswho received surgical decompression for single-segment DLSS from January 2020 to June 2022. Based on surgeon-patient discussion pre-operatively, 37 patients underwent PTE, while other 35 patients received UBE. The perioperative, follow-up and imaging data of the twogroups were compared. [Results] The PTE group proved significantly superior to the UBE group in terms of operating time [(63.2±11.0) minvs (81.2±10.3) min, P＜0.001], total length of incision [(1.0±0.2) cm vs (2.5±0.3) cm, P＜0.001], intraoperative blood loss [(39.2±10.9) ml vs(89.5±11.3) ml, P＜0.001], postoperative walk time [(1.4±0.5) days vs (2.2±0.4) days, P＜0.001], hospitalization time [(9.2±1.4) days vs (11.2±2.1) days, P＜0.001], and time to recover full weight-bearing activity [(62.2±9.5) days vs (71.1±10.2) days, P＜0.001]. The VASs for lowerback pain and leg pain, as well as ODI scores were significantly decreased in both groups over time (P＜0.05). The PTE group was signifi-cantly better than the UBE group a day postoperatively regarding to VAS score for back pain [(3.7±1.0) vs (4.3±1.1), P=0.018], VAS for legpain [(2.9±0.5) vs (3.2±0.4), P=0.007], and ODI score [(26.6±7.7) vs (30.3±5.4), P=0.022], despite of that the differences in abovesaidscores between the two groups became not statistically significant since then (P＞0.05). With respect of imaging, the canal area in bothgroups increased significantly postoperatively compared with those preoperatively (P＜0.05), but which in both groups decreased again overtime after surgery (P＜0.05). At the last follow-up, PTE group was significantly inferior to the UBE group in canal aera [(126.3±25.4) cm2 vs(163.7±28.6) cm2, P＜0.001]. There were no statistically significant differences in intervertebral space height and lumbar lordosis between the two groups at any time points accordingly (P＞0.05). [Conclusion] Both PTE and UBE can achieve good clinical efficacy in the treat-ment of DLSS. By comparison, PTE has benefits of less trauma, faster recovery, and less early postoperative low back pain and leg pain, butUBE get a wider range of decompression.